Diffuser



FIG. 1 is a top perspective view of a diffuser;

FIG. 2 is a top plan view of the diffuser of FIG. 1; and,

FIG. 3 is a bottom plan view of the diffuser of FIG. 2.

The subject matter shown in the figures above in dashed lines forms no part of the claimed invention. Further, the bottom view forms no part of the claimed invention. 

The ornamental design for a diffuser, as shown and described. 